Private patients and victims of an NHS target culture are likely to suffer the
worst in a lottery in surgery death rates, experts have warned.

A mass study of 4 million patients published yesterday found that patients are far more likely to die if they have operations at the end of the week, compared with those who undergo procedures at the start.

The figures showed that patients were 44 per cent more likely to die following an operation on a Friday than on a Monday, while those who had surgery at weekends had an increased risk of 82 per cent.

Last night Prof Sir Brian Jarman, one of the most eminent experts on hospital performance, and director of the Dr Foster Unit at Imperial College London, which carried out the research, said the data included private patients treated at NHS units, who were more likely to be treated at weekends, when consultants did private practice.

He said: “I will be interested in finding out how many of these patients were private patients, because it remains unusual for elective (planned) surgery to take place at weekends, except when it is doctors doing private practice, or else a ‘waiting list initiative’.”

Gary Walker, a former NHS trust chief executive, who lost his job at United Lincolnshire trust in 2010, after refusing to meet waiting time targets if patient safety was jeopardised, said many hospitals were put under pressure to run operating theatres at the weekends, in order to meet central targets to ensure all patient treatment is carried out within 18 weeks of referral from a GP.